After open-sourcing its JavaScript technology, Microsoft does likewise with Roslyn project and forms .Net Foundation

InfoWorld|Apr 3, 2014

Once viewed as the nemesis of open source -- and probably still seen that way by some -- Microsoft on Thursday nonetheless continued its week of gestures toward the open source community. At its Build conference, the company offered up its Roslyn compiler project to open source and formed the .Net Foundation to promote .Net technologies in open source.

These moves follow the company's open-sourcing of its WinJS JavaScript project a day earlier, also announced at the San Francisco conference. Roslyn, officially known as the .Net Compiler Platform, provides C# and Visual Basic compilers with rich code analysis APIs so that developers can build code analysis tools with the same APIs Microsoft uses to implement Visual Studio. An end-user preview of Roslyn for Visual Studio 2013 was announced as well.

"With Roslyn, you basically get a full-fidelity, complete API set that allows you to generate, transform and analyze code," allowing for experiences like better refactorings and new diagnostics, Microsoft Technical Fellow Anders Hejlsberg said. Developers using Roslyn could implement their own language features too. "Now that Roslyn is open source, it also means that Roslyn compilers can be used on other platforms," Hejlsberg added.

The core mission of Roslyn is opening the black boxes of compilers, allowing tools and end-users to share in the information compilers have about code. "Instead of being opaque source-code-in and object-code-out translators, through the .Net Compiler Platform, compilers become platforms -- APIs that you can use for code-related tasks in your tools and applications," Microsoft said on its Roslyn website.

A developer attending Build expressed surprise that Microsoft would offer Roslyn up as open source, given the company's past reputation as not being friendly toward open source. "I was shocked, actually. I didn't think Microsoft would ever do that," said Frank Lozano, senior Web developer at Cancer Treatment Centers of America. Now, people can contribute to the project, he noted. "It can only make the tools that much better."

With the launch of .Net Foundation, Microsoft seeks to contribute more projects and code into open source. "This is going to take .Net to the next level," said Scott Guthrie, Microsoft executive vice president.

The Foundation "will be the steward of a growing collection of open source technologies for .Net," the foundation website said. "We will serve as a forum for commercial and community developers alike while providing a set of practices and processes that strengthen the future of the .Net ecosystem." Current projects include .Net API for Hadoop WebClient, ASP.Net Web API, Entity Framework, and Xamarin.Mobile.

.Net Foundation follows previous Microsoft organizational efforts around open source, including the Microsoft Open Technologies group and Outercurve Foundation, formerly known as CodePlex Foundation. Asked to explain the differences between the groups, Microsoft said Outercurve is an independent foundation with a broad mission and Microsoft as a sponsor, while .Net Foundation is dedicated to increasing the collection of open source technologies for .Net. At the same time, .Net Foundation is an independent organization that will seek more sponsors.

"We found that there was enough momentum around .Net technologies to create a separate independent foundation," said Gianugo Rabellino, senior director of open source communities at Microsoft Open Technologies, in a statement. Microsoft Open Technologies is a wholly owned subsidiary of Microsoft focused on interoperability, open source, open standards, and bridging Microsoft and non-Microsoft technologies.